To ensure that the franking stamp on an envelope is clear and legible, it is customary to include an impression roller in a postage meter arranged to exert a supporting force holding the envelope against the print drum while the drum is rotating. In prior art designs of postage meter, see for example U.S. Pat. No. 3,869,986, it has been conventional to include a spring biased swingable impression roller supported on the postage meter frame and located below a lower peripheral portion of the print drum. The same arrangement can be seen in British Pat. No. 1,497,351. In a different kind of postage meter, shown in British Patent application 2,144,081, an impression roller is belt driven and provides a resilient under support for envelopes and the like so that envelopes of different thicknesses can be dealt with. An arrangement of a generally similar kind is to be seen in U.S. Pat. No. 3,823,666 of Hanson. U.S. Pat. No. 2,871,781 of Schrempp shows a letter ejecting device for use with rotary postage printing. A letter (mail piece) is ejected using a spring-driven ejection roller. A platen (impression roller is disposed opposite to a printing cylinder, and drives the ejection roller via a gear train. Other postage meter arrangements are shown in British Pat. No. 3,732,06 and U.S. Pat. No. 1,737,339.